FIG. 1 depicts an exploded view of the Trent 500 gas turbine engine showing the typical nacelle elements. The engine 56 without Nacelle is mounted to the aircraft fuselage or airframe via a pylon 14 which allows the thrust forces developed by the engine to be transmitted to the aircraft structure. The pylon 14 engages the engine 56 at a front mount 16 and a rear mount 18.
The gas turbine engine includes additional accessories, such as accessory gearboxes, accessories for gearboxes, dressings, cables, pipes, ducts, flowmeters, coolers, etc. Accessories may be driven or non-driven parts with or without fluids and with or without electrics. The accessories have significant weight and have to be mounted around the engine.
Conventionally the accessory gearboxes are mounted within the outer engine nacelle in a location beneath the engine. The gearbox is connected to the engine core via radial drive shaft. The gearbox provides power to other accessories such as an auxiliary generator or pumps for hydraulic, fuel or oil etc. systems. Other accessories are also driven by conventionally located gearboxes.
Although effective in that the gearbox is kept away from hot environment of the engine core the location of the gearbox within the outer nacelle is disadvantageous in that it requires a relatively significant amount of space within the nacelle which can increase the overall diameter of the nacelle, leading to weight and drag increase of and consequently to adverse specific fuel consumption
In alternative arrangements it is possible to locate the accessories directly to the engine core. The accessories are directly attached by brackets, short links or bosses but Inertia, vibration and thermal loads in the engine core can be transferred to the brackets or accessories and can cause premature failure or reduced reliability of those components.
It is an object of the invention to seek to provide an improved accessory mounting arrangement.